A news release earlier this month about two federal agencies launching a challenge to reduce wasted food included some statistics that are bound to remind many people of their mothers’ admonition to “Clean your plate. You shouldn’t let that food go to waste.”

The U.S. Food Waste Challenge is a joint effort of the U.S. Department of Agriculture and the Environmental Protection Agency: the people who produce the food and those concerned about what happens to the food that’s thrown away.

According to the EPA, Americans waste 30 to 40 percent of their food. That’s a shocking amount of food being thrown out rather than consumed by hungry people. Once that food arrives at landfills across the country, it begins to decompose, creating large amounts of methane that contribute to damaging greenhouse gases.

Another surprising statistic: The 35 million tons of food Americans send to landfills and incinerators every year represents the largest single category of solid waste, even higher than paper and plastic. In addition to the impact of discarded food, the agencies also note the front-end waste of energy to produce and transport food that eventually is thrown away.

The Food Waste Challenge is taking a multifaceted approach to this problem, working with producers, processors, manufacturers, retailers and consumers to promote efforts to reduce, recover and recycle food waste. They are looking at ways to reduce waste in school meals programs and to educate consumers about food waste and food storage. One more statistic: The amount of food wasted in American homes and restaurants was valued at $390 per U.S. consumer in 2008.

Reducing this waste is a big challenge, but it’s also an effort that can benefit from individuals simply being more conscious of the quantity of food they purchase, consume and throw away. There’s more to it than simply cleaning your plate, but the food waste statistics seem to confirm that your mother had the right idea.